<template>
  <div class="spec-preview">
    <img :src="ImageUrl" />
    <div class="event" @mousemove="maskMove"></div>
    <div class="big">
      <img :src="ImageUrl" ref="bigImg" />
    </div>
    <div class="mask" ref="mask"></div>
  </div>
</template>

<script>
export default {
  name: "Zoom",
  props: ["ImageUrl"],
  methods: {
    maskMove(e) {
      // console.log(e.offsetX);
      let x = e.offsetX - 100;
      let y = e.offsetY - 100;
      if (x <= 0) {
        x = 0;
      } else if (x >= 200) {
        x = 200;
      }
      if (y <= 0) {
        y = 0;
      } else if (y >= 200) {
        y = 200;
      }

      this.$refs.mask.style.left = x + "px";
      this.$refs.bigImg.style.left = -x * 2 + "px";
      this.$refs.mask.style.top = y + "px";
      this.$refs.bigImg.style.top = -y * 2 + "px";
    },
  },
};
</script>

<style lang="less" scoped>
.spec-preview {
  position: relative;
  width: 400px;
  height: 400px;
  border: 1px solid #ccc;

  img {
    width: 100%;
    height: 100%;
  }

  .event {
    width: 100%;
    height: 100%;
    position: absolute;
    top: 0;
    left: 0;
    z-index: 998;
  }

  .mask {
    width: 50%;
    height: 50%;
    background-color: rgba(0, 255, 0, 0.3);
    position: absolute;
    left: 0;
    top: 0;
    display: none;
  }

  .big {
    width: 100%;
    height: 100%;
    position: absolute;
    top: -1px;
    left: 100%;
    border: 1px solid #aaa;
    overflow: hidden;
    z-index: 998;
    display: none;
    background: white;

    img {
      width: 200%;
      max-width: 200%;
      height: 200%;
      position: absolute;
      left: 0;
      top: 0;
    }
  }

  .event:hover ~ .mask,
  .event:hover ~ .big {
    display: block;
  }
}
</style>